The peroneal tendons arise from muscles within the lateral (outside) compartment of the leg. These tendons run behind the lateral (outside) malleolus (ankle bone) and then insert into the foot on the lateral (outside) and plantar (underneath) to attach to the bones. The peroneal tendons are the primary evertors, which produce eversion when needed. These tendons are kept in place behind the lateral malleolus with support of a fibro-osseous tunnel. This tunnel is formed by the ankle bones, ankle ligaments and the peroneal retinaculum. The tendons are then able to glide within the tunnel as needed for foot function. During trauma, for example a sprained ankle, the retinaculum may pull away from its attachment to bone or may rupture. The disruption of the tunnel may allow the peroneals to move outside of the normal boundries producing a subluxation of the peroneal tendons.
Symptoms of a subluxed peroneal typically are pain and swelling to the outside of the ankle. In fact most injuries are misdiagnosed as an ankle sprain. When the initial symptoms have lessened and the person is able to walk on the foot, they may feel a snapping or popping sensation along the outside of the ankle. Sometimes on visual examination you can actually see the peroneals tendons popped out of the tunnel and over the outer ankle bone. This may lead to an unstable ankle with frequent ankle sprains if not treated.
Causes of a bunion are due to a number of things. Your foot structure you were born with is probably the most causative factor. Foot structure is hereditary, external factors may cause symptoms to develop faster. Pronation is a term used to describe a foot which allows the arch to fall more than normal and is commonly associated with the formation of a bunion. Narrow toed dress shoes and high heel shoes may contribute to the formation. Other types of arthritis such as Rheumatoid or Psoriatic Arthritis may cause bone destruction where misalignment of the joints is also seen forming a bunion. Neuromuscular diseases may affect the pull and normal function of the muscles and tendons in your foot causing an imbalance and deformation of the foot structure. If one leg is longer or shorter than the other the structure of the foot is also affected. Trauma or surgery to the bones and muscles in the foot can cause structure damage as well.
Podiatric Care usually begins with x-rays to examine the bone structure for associated fractures or dislocations. The initial injury will probably be treated like an ankle sprain with compression, ice, elevation, and non-weight bearing. Surgery may be indicated for initial treatment of a subluxed peroneal in some situations. This is mostly dependent on your activity level and severity of injury. A chronic (old) injury may conservatively be treated first with shoe modifications, orthotics or other types of bracing.
Surgery to correct subluxed peroneal tendons usually involves a direct repair of soft tissue, or cuts into the bone to form a deeper tunnel. Most often the procedure will involve both aspects. This might involve pins, screws, wires, or anchors. Your podiatrist will give you advise on this.
Post-operative Care and Risks of surgery for subluxed peroneals may vary as the procedure varies. You may need a cast to protect you for a short time. Sometimes a soft bandage with a post-operative shoe is allowed. More often the procedure requires a cast below the knee to keep the peroneal muscles in your leg from firing. You should expect some pain following surgery as well as swelling. Especially for the first 48 hours you should keep your leg elevated and occasional ice placed over the area of surgery (about 20 minutes per hour). Surgical cuts are made through the skin so a scar is expected. If you are a keloid former, let your surgeon know. Surgical cuts are not only made through skin, but through other layers of tissue as well, a scar may form within your foot and lead to adhesions. You may use crutches, a walker, or wheelchair to help you keep weight off of this foot. Healing time is typically 6-8 weeks for all bone cuts. This is influenced by many factors including your nutrition, circulation, and other medical conditions. If you are a smoker you can expect to take longer to heal. If you are required to keep pressure off of your foot your leg muscles are not being used as they were before surgery. This allows for slower movement of the blood through the leg vessels. Occasionally this can lead to a blood clot in the leg which can become life threatening. Hip and knee flexion and extension exercises as well as wiggling your toes gently can help prevent this from occurring. If you have a history of blood clots you should let your surgeon know.